def retained_batch_head
import bendvy-ecs-core@0.1.0.4/event_notice_runtime.bend as EventNoticeRuntimeimport Base
71def retained_batch_head(~P:Data,~F:Type,rest:F -> Retention<P,F>,tick:Nat,returned:F & (List<&2,P> & List<&2,List<&2,P>>)) -> Retention<P,F>:
72 match returned:
73 case (family,(+records,slots)):retained_batch_join(~P,~F,tick,records,slots,rest(family))